title: Unimolecular dissociation reactions of methyl benzoate radical cation.
abstract: The blackbody infrared radiation induced dissociation of methyl benzoate (C8H8O2(+*)) radical cation was investigated by using a Fourier transfer ion cyclotron resonance mass spectrometer equipped with a resistively heated (wire temperatures of 400-1070 K) wire ion guide. We observed product ion branching ratios that are strongly dependent upon wire temperature. At low temperatures (670-890 K) the major product ion C7H8 (+*) (m/z 92), which is formed by loss of CO2, and at higher temperatures (above 900 K), loss of methoxy radical ((*)OCH3) competes with loss of CO2. The energies of the various reactant ions and transition states for product ion formation were estimated by using density functional theory molecular orbital calculations, and a proposed mechanism for the dissociation chemistry of C8H8O2 (+*) involving a multistep rearrangement reaction is tested using the Master Equation formalism.
authors.affiliation: Department of Chemistry, The Laboratory for Biological Mass Spectrometry, Texas A&M University, College Station, Texas 77842, USA.
authors.forename: Yiqun
authors.initials: Y
authors.lastname: Huang
authors.forename: Scott
authors.initials: S
authors.lastname: Peterman
authors.forename: Shane E
authors.initials: SE
authors.lastname: Tichy
authors.forename: Simon W
authors.initials: SW
authors.lastname: North
authors.forename: David H
authors.initials: DH
authors.lastname: Russell
mesh_terms: D001565:Benzoates / Q000737:chemistry*; D005583:Fourier Analysis; D006859:Hydrogen / Q000737:chemistry; D007259:Infrared Rays; D007700:Kinetics; D011789:Quantum Theory; D013696:Temperature; D013816:Thermodynamics
chemical_list: D001565:Benzoates; C044605:methyl benzoate; D006859:Hydrogen